INITIAL drilling at Kusi prospect of Pacific Niugini’s Garaina Gold Project, has added support to the possibility of discovering a large-scale epithermal gold and porphyry copper-gold system. Garaina is in the Owen Stanley Ranges, about 70km southeast of the Hidden Valley mine.
Assay results have been received from the first 131 metres in the initial hole and epithermal gold mineralization was intersected. Best result was 20 metres @ 2.89 grams/tonne from 107 metres, including 11 metres @ 4.72 grams/tonne from 114 metres. The hole was drilled to 376.8 metres and the company is awaiting remaining assays.
The hole displayed porphyry diorite lithology in the first 70 metres with anomalous copper grades and elevated molybdenum. Intense argilic and potassic alteration typical of a porphyry intrusion were noted in both the porphyritic sections of the hole and in altered sediments, thought to be potentially fringing the porphyry target.
Since completion of this hole, a second hole was commenced and drilled to 98.8 metres down hole. Unfortunately the drill string was jammed, broke and became unrecoverable. The third hole is in progress and by late November had advanced about 90 metres. In both latter holes geologists have noted similar mineralization to that in the initial hole.
Structural interpretation suggests a substantial transfer fault system bisects the Owen Stanley Ranges at Garaina creating structural weaknesses which have been subject to intrusion and rising epithermal fluids. These areas manifest in significant magnetic anomalies.
Reconnaissance field work over the last three years defined substantial anomalism, with trenching returning long runs of gold mineralization within outcropping meta-sedimentary rocks. Trenching results include 71 metres @ 4.96 grams/tonne gold, 4.77 grams/tonne silver and 0.37% copper; 34 metres @ 3.29 grams/tonne gold and 39.17 grams/tonne silver; 20 metres @ 2.67 grams/tonne gold and 0.30% copper; and 11 metres @ 2.45 grams/tonne gold and 8.92 grams/tonne silver.
Three stratigraphic holes were then drilled to define subsurface geology and test persistence of the trenching results. All holes returned gold mineralization but without sign of the expected intrusive bodies. Later magnetic data suggests the holes were drilled outside the intrusive target zones. Best results were 7.8 metres @ 1.83 grams/tonne gold and 8.84 grams/tonne silver, and 10.1 metres @ 2.39 grams/tonne gold, 4.08 grams/tonne silver and 0.25% copper.
Pacific Niugini believes Kusi displays a number of analogues to the Wafi porphyry copper-gold and epithermal gold-silver deposit with the structural setting being very similar.
Garaina is the subject of a farm-out agreement with MGL Ltd with Pacific Niugini undertaking field work on MGL’s behalf. Under the agreement, MGL will spend $6 million to earn 50.1% of the project.